; a generic but proper use of dbs
; Memory positions know look suspiciously like variable names
        jmp     start               ;now we know to jump over our data!
jan     db   40
feb     db   50
tot     db   ?

start:  mov  al, jan                ;Note that although we would like to write: add jan, feb
        add  al, feb                ; we can't because that would be memory to memory!!
        mov  tot, al

        int  20h